862 research outputs found
Checklist of British and Irish Hymenoptera - aculeates (Apoidea, Chrysidoidea and Vespoidea)
Background: The checklist of British and Irish aculeate Hymenoptera (Apoidea, Chrysidoidea and Vespoidea) is revised. Species distribution is summarised for all species at the level of country (England, Scotland, Wales, Ireland and Isle of Man).
New information: The 601 native species represent an increase of 25 on the 1978 checklist, comprising mostly new discoveries. This increase is nearly balanced by the 23 species now presumed to be extinct in Britain and Ireland.This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY
4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are
credited.NHM Repositor
Size Effects in Cone Penetration Tests in Sand
Size effects in miniature cone penetration tests (CPTs) are examined by performing a series of 1 g laboratory tests using three penetrometers of 3, 6, and 12 mm in diameter (D) in two grades of dry Leighton Buzzard sand respectively. It is found that the size effects primarily depend on three non-dimensional geometrical parameters, including relative penetration depth (H/D), normalised surface roughness of the cone (Ra/d50), and normalized cone size (D/d50). Test results showed that: (1) H/D is a major size factor influencing the cone resistance at relatively shallow depths, and its influence may disappear while the localized failure mechanism dominates. (2) the cone resistance may increase with a decreasing value of D/d50 in some circumstances, and this effect attenuates in loose sand; (3) the cone resistance is positively related to Ra/d50, especially for cones with an intermediate rough interface. These size dependent behaviour is attributed to the dependency of the failure pattern and sand properties on the stress level, strain level, and non-local interactions of underlying microstructures and the dependency of the shearing resistance of sand-cone interface on Ra/d50
Investigating the effects of particle shape on normal compression and overconsolidation using DEM
Discrete element modelling of normal compression has been simulated on a sample of breakable two-ball clumps and compared to that of spheres. In both cases the size effect on strength is assumed to be that of real silica sand. The slopes of the normal compression lines are compared and found to be consistent with the proposed equation of the normal compression line. The values of the coefficient of earth pressure at rest K0,nc are also compared and related to the critical state fiction angles for the two materials. The breakable samples have then been unloaded to establish the stress ratios on unloading. At low overconsolidation ratios the values of K0 follow a well-established empirical relationship and realistic Poisson ratios are observed. On progressive unloading both samples head towards passive failure, and the values of the critical state lines in extension in q–p' space are found to be consistent with the critical state angles deduced from the values of K0 during normal compression. The paper highlights the important role of particle shape in governing the stress ratio during both normal compression and subsequent overconsolidation
DEM of triaxial tests on crushable sand
This paper presents simulations of high-pressure triaxial shear tests on a crushable sand. The discrete element method is used, featuring a large number of particles and avoiding the use of agglomerates. The triaxial model features a flexible membrane, therefore allowing realistic deformation, and a simple breakage mechanism is implemented using the octahedral shear stress induced in the particles. The simulations show that particle crushing is essential to replicate the realistic behaviour of sand (in particular the volumetric contraction) in high-pressure shear tests. The general effects of crushing during shear are explored, including its effects on critical states, and the influence of particle strength and confining pressure on the degree of crushing are discussed
MYELOPATHY SECONDARY TO AORTOCAVAL FISTULA IN A CAT
A 15-month-old neutered male cat was presented for progressive paraparesis of 3 months' duration and suspected cardiomegaly. Neuroanatomical localization was a T3-L3 myelopathy. On abdominal ultrasound, an anomalous vessel with turbulent blood flow was identified arising from the caudal vena cava. Myelography showed a bilateral ventrolateral extradural spinal cord compression from T12 to L4. Nonselective angiography and contrast-enhanced computed tomography clearly indicated a vascular complex and vena caval aneurysm with an engorged internal vertebral venous plexus. Surgical occlusion of the anomalous vessels was unsuccessful
Early star-forming galaxies and the reionization of the Universe
Star forming galaxies represent a valuable tracer of cosmic history. Recent
observational progress with Hubble Space Telescope has led to the discovery and
study of the earliest-known galaxies corresponding to a period when the
Universe was only ~800 million years old. Intense ultraviolet radiation from
these early galaxies probably induced a major event in cosmic history: the
reionization of intergalactic hydrogen. New techniques are being developed to
understand the properties of these most distant galaxies and determine their
influence on the evolution of the universe.Comment: Review article appearing in Nature. This posting reflects a submitted
version of the review formatted by the authors, in accordance with Nature
publication policies. For the official, published version of the review,
please see http://www.nature.com/nature/archive/index.htm
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Older adult experience of care and staffing on hospital and community wards: a cross-sectional study
BACKGROUND: Recent major concerns about the quality of healthcare delivered to older adults have been linked to inadequate staffing and a lack of patient-centred care. Patient experience is a key component of quality care - yet there has been little research on whether and how staffing levels and staffing types affect satisfaction amongst older adult hospital inpatients. This study aimed to evaluate the association between registered nurse and healthcare assistant staffing levels and satisfaction with care amongst older adult hospital inpatients, and to test whether any positive effect of higher staffing levels is mediated by staff feeling they have more time to care for patients.
METHODS: Survey data from 4928 inpatients aged 65 years and older and 2237 medical and nursing staff from 123 acute and community medical wards in England, United Kingdom (UK) was collected through the Royal College of Psychiatrist's Elder Care Quality Mark. The cross-sectional association between staffing ratios and older adult patient satisfaction, and mediation by staff perceived time to care, was evaluated using multi-level modelling, adjusted for ward type and with a random effect for ward identity.
RESULTS: Higher numbers of patients per healthcare assistant were associated with poorer patient satisfaction (adjusted β = - 0.32, 95% CI - 0.55 to 0.10, p < 0.01), and this was found to be partially mediated by all ward staff reporting less time to care for patients (adjusted β = - 0.10, bias-corrected 95% CI - 1.16 to - 0.02). By contrast, in both unadjusted and adjusted models, the number of patients per registered nurse was not associated with patient satisfaction.
CONCLUSIONS: Older adult hospital patients may particularly value the type of care provided by healthcare assistants, such as basic personal care and supportive communication. Additionally, higher availability of healthcare assistants may contribute to all ward staff feeling more able to spend time with patients. However, high availability of registered nurses has been shown in other research to be vital for ensuring quality and safety of patient care. Future research should seek to identify the ideal balance of registered nurses and healthcare assistants for optimising a range of outcomes amongst older adult patients
Intervals of Intense Energetic Electron Beams Over Jupiter's Poles
Juno's Jupiter Energetic particle Detector Instrument often detects energetic electron beams over Jupiter's polar regions. In this paper, we document a subset of intense magnetic field‐aligned beams of energetic electrons moving away from Jupiter at high magnetic latitudes both north and south of the planet. The number fluxes of these beams are often dominated by electrons with energies above about 1 MeV. These very narrow beams can create broad angular responses in the Jupiter Energetic particle Detector Instrument with unique signatures in the detector count rates, probably because of >10 MeV electrons. We use these signatures to identify the most intense beams. These beams occur primarily above the swirl region of the polar cap aurora. This polar region is described as being of low brightness and high absorption and the most magnetically “open” at Jupiter
Consensus Paper—ICIS Expert Meeting Basel 2009 treatment milestones in immune thrombocytopenia
The rarity of severe complications of this disease in children makes randomized clinical trials in immune thrombocytopenia (ITP) unfeasible. Therefore, the current management recommendations for ITP are largely dependent on clinical expertise and observations. As part of its discussions during the Intercontinental Cooperative ITP Study Group Expert Meeting in Basel, the Management working group recommended that the decision to treat an ITP patient be individualized and based mainly on bleeding symptoms and not on the actual platelet count number and should be supported by bleeding scores using a validated assessment tool. The group stressed the need to develop a uniform validated bleeding score system and to explore new measures to evaluate bleeding risk in thrombocytopenic patients—the role of rituximab as a splenectomy-sparing agent in resistant disease was also discussed. Given the apparently high recurrence rate to rituximab therapy in children and the drug's possible toxicity, the group felt that until more data are available, a conservative approach may be considered, reserving rituximab for patients who failed splenectomy. More studies of the effectiveness and side effects of drugs to treat refractory patients, such as TPO mimetics, cyclosporine, mycophenolate mofetil, and cytotoxic agents are required, as are long-term data on post-splenectomy complications. In the patient with either acute or chronic ITP, using a more personalized approach to treatment based on bleeding symptoms rather than platelet count should result in less toxicity and empower both physicians and families to focus on quality-of-life
Responsiveness and minimal clinically important difference for pain and disability instruments in low back pain patients
BACKGROUND: The choice of an evaluative instrument has been hampered by the lack of head-to-head comparisons of responsiveness and the minimal clinically important difference (MCID) in subpopulations of low back pain (LBP). The objective of this study was to concurrently compare responsiveness and MCID for commonly used pain scales and functional instruments in four subpopulations of LBP patients. METHODS: The Danish versions of the Oswestry Disability Index (ODI), the 23-item Roland Morris Disability Questionnaire (RMQ), the physical function and bodily pain subscales of the SF36, the Low Back Pain Rating Scale (LBPRS) and a numerical rating scale for pain (0–10) were completed by 191 patients from the primary and secondary sectors of the Danish health care system. Clinical change was estimated using a 7-point transition question and a numeric rating scale for importance. Responsiveness was operationalised using standardardised response mean (SRM), area under the receiver operating characteristic curve (ROC), and cut-point analysis. Subpopulation analyses were carried out on primary and secondary sector patients with LBP only or leg pain +/- LBP. RESULTS: RMQ was the most responsive instrument in primary and secondary sector patients with LBP only (SRM = 0.5–1.4; ROC = 0.75–0.94) whereas ODI and RMQ showed almost similar responsiveness in primary and secondary sector patients with leg pain (ODI: SRM = 0.4–0.9; ROC = 0.76–0.89; RMQ: SRM = 0.3–0.9; ROC = 0.72–0.88). In improved patients, the RMQ was more responsive in primary and secondary sector patients and LBP only patients (SRM = 1.3–1.7) while the RMQ and ODI were equally responsive in leg pain patients (SRM = 1.3 and 1.2 respectively). All pain measures demonstrated almost equal responsiveness. The MCID increased with increasing baseline score in primary sector and LBP only patients but was only marginally affected by patient entry point and pain location. The MCID of the percentage change score remained constant for the ODI (51%) and RMQ (38%) specifically and differed in the subpopulations. CONCLUSION: RMQ is suitable for measuring change in LBP only patients and both ODI and RMQ are suitable for leg pain patients irrespectively of patient entry point. The MCID is baseline score dependent but only in certain subpopulations. Relative change measured using the ODI and RMQ was not affected by baseline score when patients quantified an important improvement
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